Commercially available bone fixation devices are often made of metal alloys which must be surgically removed after bone healing. The removal of such devices causes additional trauma to the patient as well as increased medical costs. Metallic devices also have moduli of elasticity which are 10-20 times higher than that of cortical bone, thus preventing the loading of the bone and possibly causing osteopenia due to stress shielding.
U.S. Pat. Nos. 4,539,981 and 4,550,449 to Tunc (the inventor of the present invention) relate to absorbable bone fixation devices made from high molecular weight polymer of L-lactide. However, such fixation devices have a relatively low rate of absorption and retain relatively high tensile strength after the bone fully heals.
U.S. Pat. No. 5,569,250 to Sarver et al. relates to a biocompatible osteosynthesis plate for securing a plurality of adjacent bone portions. It purportedly discloses, inter alia, non-reinforced lactide and glycolide copolymer (see, e.g., col. 6, lines 63 et seq.). However, such materials exhibit relatively low tensile strengths.
All documents cited herein, including the foregoing, are incorporated herein by reference in their entireties for all purposes.